Hi,
I'm trying to play around with 0.8.0-rc1 and counters, and I'm a
little confused.
First question I have is about the definition. A column within a
standard column family cannot be a counter column type?
I had tried the following, with no success.
create column family urlcounts
with comparator = UTF8Type
and default_validation_class = LongType
and column_metadata=[
{ column_name:count,
validation_class:CounterColumnType
}
];
The only successful way was for me to create a new column family with
a default validation class of "CounterColumnType":
create column family counters with default_validation_class = CounterColumnType;
Now I have a column family with counters:
Keyspace: sdo:
Replication Strategy: org.apache.cassandra.locator.NetworkTopologyStrategy
Options: [datacenter1:1]
Column Families:
ColumnFamily: counters
Key Validation Class: org.apache.cassandra.db.marshal.BytesType
Default column value validator:
org.apache.cassandra.db.marshal.CounterColumnType
Columns sorted by: org.apache.cassandra.db.marshal.BytesType
Row cache size / save period in seconds: 0.0/0
Key cache size / save period in seconds: 200000.0/14400
Memtable thresholds: 0.2953125/63/1440 (millions of ops/MB/minutes)
GC grace seconds: 864000
Compaction min/max thresholds: 4/32
Read repair chance: 1.0
Replicate on write: false
Built indexes: []
>From the CLI, I insert / increment a [key][column] in this column family:
incr counters[ascii('foo')][ascii('c1')];
Second question: If I want to implement counters, they have to exist
in a seperate column family from the rest of my data?
--
Sasha Dolgy
[email protected]
